Currently experimenting with Dynaglide main rope with UCR, using mitten hook (a la Griz) to attach prussik of 3/32" bungee cord to tail of UCR. Looks just like Opie's picture, but with bungee and mitten hook. So far so good. I use a structural ridgeline, so force on UCR increases with greater distance between trees. Next test will use trees about 27' apart.